An object's angular momentum changes by 10 kg-m^2/s in 2.0 s. What magnitude average torque acted on this object? * a. 5 Nm ОБ. 10 Nm О с. 20 Nm O d. 40 Nm ****A wheel of moment of inertia of 5.00 kg-m^2 starts from rest and accelerates under a constant torque of 3.00N-m for 8.00 s. What is the wheel's rotational kinetic energy at the end of 8.00 s? * а. 57.6 J O b. 78.8 J O c. 91.9 J O d. 122.0 J

An object's angular momentum changes by 10 kg-m^2/s in 2.0 s. What magnitude average torque acted on this object? * a. 5 Nm ОБ. 10 Nm О с. 20 Nm O d. 40 Nm ****A wheel of moment of inertia of 5.00 kg-m^2 starts from rest and accelerates under a constant torque of 3.00N-m for 8.00 s. What is the wheel's rotational kinetic energy at the end of 8.00 s? * а. 57.6 J O b. 78.8 J O c. 91.9 J O d. 122.0 J

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter10: Rotational Motion And Angular Momentum

Section: Chapter Questions

Problem 5CQ: The moment of inertia of a long rod spun around an axis through one end perpendicular to its length...

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A cylinder with moment of inertia I1 rotates with angular velocity 0 about a frictionless vertical axle. A second cylinder, with moment of inertia I2, initially not. rotating, drops onto the first cylinder (Fig. P8.73). Because the surfaces are rough, the two cylinders eventually reach the same angular speed . (a) Calculate . (b) Show that kinetic energy is lost in this situation, and calculate the ratio of the final lo the initial kinetic energy. Figure P8.73
While punting a football, a kicker rotates his leg about the hip joint. The moment of inertia of the leg is 3.75kgm2 and its rotational kinetic energy is 175 J. (a) What is the angular velocity of the leg? (b) What is the velocity of tip of the punter’s shoe if it is 1.05 m from the hip joint?
While punting a football, a kicker rotates his leg about the hip joint. The moment of inertia of the leg is 3.75kg-m2 and its rotational kinetic energy is 175 J. (a) What is the angular velocity of the leg? (b) What is the velocity of tip of the punter's shoe if it is 1.05 m from the hip joint? (c) Explain how the football can be given a velocity greater than the tip of the shoe (necessary for a decent kick distance).
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During a very quick stop, a car decelerates at 7.00 m/s2. (a) What is the angular acceleration of its 0.280-m-radius tires, assuming they do not slip on the pavement? (b) How many revolutions do the tires make before coming to rest, given their initial angular velocity is 95.0 rad/s? (c) How long does the car take to stop completely? (d) What distance does the car travel in this time? (e) What was the car's initial velocity? (f) Do the values obtained seem reasonable, considering that this stop happens very quickly?
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